Sectionalized mast hoist apparatus



Jan. 29, 1957 G. W. GILLS SECTIONALIZED MAST HOIST APPARATUS Filed March 16, 1954 INVENTOR d. hwy/9 ATTORNEYS United States 2,779,569 SECTIONALIZED MAST HOIST APPARATUS Golden W. Gills, Bluefield, W. Va.

Application March 16, 1954, Serial No. 416,608

2 Claims. (Cl. 254-148) The present invention relates in general to hoist apparatus and more particularly to hoist mechanisms for multiple section tubular masts.

An object of the present invention is the provision of a novel transportable hoist mechanism for elevating sectionalized masts for antennas and the like to desired vertical positions characterized by simplicity of construction and operation and ease of association of the hoist structure with the mast sections.

Another object of the present invention is the provision of a novel hoist mechanism for elevating sectionalized antenna masts to a desired vertical position, wherein the hoist mechanism is capable of elevating individual mast sections to vertical positions where additional sections can be joined thereto in supporting relation to the first mentioned sections.

Another object of the present invention is the provision of a novel hoist mechanism for elevating sectionalized television antenna masts wherein a vertically shiftable clamping mechanism is provided which is selectively engageable with individual antenna mast sections to elevate successive sections of the mast into position in a novel and advantageous manner.

Another object of the present invention is the provision of a hoist mechanism for television antenna masts having novel clamping means provided therein which is associated with the antenna mast in sliding or lifting relation therewith in response to the direction of travel of the clamping means.

Other objects, advantages and capabilities of the present invention may become apparent from the following detailed description, taken in conjunction with the accompanying drawing, showing a preferred embodiment of the invention.

In the drawing:

Figure 1 is a perspective view of a hoist mechanism embodying the present invention illustrated in operative association with a sectionalized television antenna mast.

Figure 2 is a horizontal transverse section view of the hoist mechanism and clamping assembly provided therein, taken along the lines 2--2 of Figure 1.

Figure 3 is a fragmentary vertical longitudinal section view of the hoist mechanism and antenna mast associated therewith, taken along the lines 4-4 of Figure 2; and

Figure 4- is a fragmentary vertical transverse section view of the clamping assembly incorporated in the hoist mechanism, taken along the lines 44 of Figure 2.

Referring to the drawing, wherein like reference characters designate corresponding parts throughout the several figures, the hoist mechanism, generally indicated by the reference character 10, comprises a hollow pipe section 11 preferably of the order of 13 to 14 feet in length and 6 inches in diameter, having a base 12 formed of cylindrical shape in the preferred embodiment secured to the lower end thereof and designed to be supported in use in vertical position standing on the base 12 by means of suitable guy wires 13 coupled to an annular flange 14 positioned on the pipe 11 adjacent the upper 2,779,569 Patented Jan. 29, 1957 end thereof. The pipe section 11 is provided with an elongated slot 15 extending through the side wall of the pipe and aligned with the axis thereof. In the preferred embodiment, the slot 15 is approximately /1 of an inch in width and 10 feet 4 inches long. Within the bore of the pipe section 11 is provided a heavy guide block 16, preferably of cylindrical form having a diameter complementary to the internal diameter of the pipe 11. The block 16 is provided with an arm 17 of the width of the slot 15 and projects through the slot to a point immediately outwardly of the wall of the pipe 11 and an upwardly projecting car 18. A suitable cable or rope 19 is secured at one end to the ear 18 of the guide block 16 and extends through the open upper end of the pipe 11 and about an idler pulley 20 journalled on a bifurcated arm 21 welded to the wall of the pipe 11 and projecting from the upper end thereof, the opposite end portion of the cable 19 being trained about and secured to the drum of a suitable crank 22 supported on a bracket 23 fixed to the outer wall pipe 11 at a conveniently accessible height. A clamping assembly 25 is carried by the guide block 16 externally of the pipe 11 for engaging and elevating the individual tubular or circular cross section sections 26 of a mast 27 for supporting an antenna, an antenna array or the like, the sections 26 being of the type having an internally threaded socket 26 at the upper end thereof and an externally threaded lower end 26". The clamping assembly 25 preferably comprises an outwardly opening U-shaped frame 28 lying in a horizontal plane with the bridge portion 29 of the frame 28 secured to the arm 17 of the guide block 16 projecting through the slot 16 by means of suitable screws or the like. Between the parallel outwardly projecting arms 30 and 31 of the frame 28 are provided a pair of facing jaws 32 and 33 having serrated concave gripping faces 34 and 35 defining when the jaws 32 and 33 lie in coplanar relation with the frame 28 an elliptical opening having a somewhat shorter minor axis parallel to the bridge 29 of the frame 28 than the diameter of the pipe sections 26 to be handled. The jaws 32 and 33 are hinged to the parallel arms 30 and 31 of the frame 28 to pivot only in an upward direction from a horizontal position lying in the plane of the frame 28 by means of hinge ears 36 pivotally coupled to straps 37 by means of hinge pins 38, the straps 37 being adjustably supported on the arms 30 and 31 of the frame 28 by means of bolts 39 extending through slots disposed longitudinally of the straps 37. A conventional split ring guide bracket 40 of circular cross section is supported at the upper end of the pipe section 11 and pro jects therefrom in vertical alignment with the space defined between the gripping surfaces of the jaws 32 and 33 to receive and guide the mast sections 26 vertically along the pipe 11.

In the use of the instant hoist mechanism, the pipe section 11 of the hoist is supported in vertical position adjacent the desired location for the antenna mast 27 with its base 12 disposed against the ground or the roof of a building on which the mast is to be supported, and the pipe section 11 is steadied in vertical position by means of guy wires 13. A tubular section 26 designed to form the uppermost section of the mast 27, which sections are normally commercially supplied in 10-foot lengths, is disposed in erect position beside the pipe section 11 of the hoist and the lower end 26 is projected through the opening defined between the gripping surfaces 34, 35 of the jaws 32, 33 with the jaws pivoted upwardly on their hinges to define an opening therebetween suil'lcient to receive the pipe section. Upon release of the upwardly pivoted jaws 32 and 33, the gripping surfaces 34 and 35 of the jaws drop into engagement with the sides of the pipe section 26. Upon rotation of the crank arm of the crank 22 to wind the cable 19 about the drum of the crank, the guide block 16 will be shifted vertically in the bore of the tubular section 11 elevating the clamping frame 28 along with the guide block 15. The force of gravity upon the jaws 32 and 33 in conjunction with the weight of the tubular section as of the mast 27 produces intimate gripping contact between the serrated gripping surfaces 34 and 35 of the jaws 32 and 33 and the walls of the tubular section 26, so that the lower portion of the tubular section 26 is lifted vertically by the clamping unit 25 to a position adjacent the upper limit of the slot 15 upon operation of the crank 22. The upper portion of the tubular section 26 of the mast is guided vertically through the guide bracket 49 so as to maintain the tubular section 26 in proper vertical alignment during lifting of the lower end thereof.

The upper limit of movement of the clamping unit 25 is located at a sufiicient height from the base 12 of the hoist mechanism so that when the clamping unit is at its upper limit of travel, the lower externally threaded end of the tubular antenna mast section as is supported a sufiicient height above the base 12 to permit another antenna mast section 26 to be disposed in vertical position between the lower end 26 of the elevated antenna mast section of the base 12. The internally threaded socket 26 at the upper end of the second antenna mast section 26 may then be threaded into connected relation with the next upper antenna mast section, and the lower end of the second section 26 lowered into contact with the base 12 to support the uppermost section 26 in elevated position. Upon reversing the direction of rotation of the crank 22 to lower the guide block 16 and clamping assembly 25' to its lower limit of travel in the slot 1.5, the pivotal movement permitted by the hinges supporting the jaws 32 and 33 is in the same direction as the relative movement of the walls of the mast section 26 relative to the clamping surfaces 34 and 35 so that the clamping jaws 32 and 33 merely ride over the walls of the mast section 26 and permit the clamping unit 25 to slide to the lower end of the slot 15. When the crank 22 is again operated to elevate the guide block 16 and clamping assembly 25, the force of gravity and the weight of the antenna mast sections on the clamping jaws 32 and 33 will again bring them into clamping relation with the walls of the mast section 25 to elevate the two joined sections in the same manner as described in connection with elevation of the first section. Any number of antenna mast sections 26 may be joined to the preceding sections and elevated in the same manner.

While but one particular embodiment of the invention has been particularly shown and described, it is apparent that various modifications may be made in the invention without departing from the spirit and scope thereof, and it is desired, therefore, that only such limitations shall be placed thereon as are imposed by the prior art and are set forth in the appended claims.

I claim:

1. Hoist apparatus for elevating tubular mast sections of the type having threaded ends adapted to permit interconnection of successive sections to secure the sections in an aligned series comprising a hollow tubular post having an elongated slot in the wall thereof extending substantially the length of said post, means for supporting said post in vertical position, a block slidably mounted in the hollow of said post, cable winding means mounted on said post, a cable extending between said cable winding means and said block for elevating and lowering said block within said post, clamping means projecting laterally from said post and secured to said block through said slot,

said clamping means having a pair of clamping jaws pivoted for upward swinging movement for engaging tubular mast sections therebetween and elevating the same upon elevation of said block, means for urging said jaws toward each other into clamping engagement with said sections in response to the weight of said sections upon upward movement of said clamping means and for shifting said jaws into freely sliding relation with said sections on downward movement of said clamping means, and guide means projecting laterally from the upper end of said post for maintaining mast sections engaged by said clamping jaws in vertical alignment with said post, said slot being of a length at least as great as the length of the mast sections to be hoisted to enable said clamping means to engage a lower end portion of the mast section at its lower limit of travel and elevate the lower end portion to a suflicient height at the upper limit of travel of said clamping means to enable another mast section to be disposed below and in alignment with the elevated section and their threaded ends intercoupled while the elevated section is held by said clamping means.

2. Hoist apparatus for elevating tubular mast sections of the type having threaded ends adapted to permit interconnection of successive sections to secure the sections in an aligned series comprising a hollow tubular post having an elongated slot extending through the wall of said post for substantially the length thereof, means for supporting said post in vertical position on one end thereof, an elevator cylinder slidably supported in the hollow of said post, a pulley rotatably mounted at the top of said post, a cable winding crank supported on the exterior of said post, a cable trained over said pulley with one end secured to said block and the other end to said cable winding crank, a horizontal frame projecting from said post having means extending through said slot for supporting said frame from said elevator cylinder and a pair of laterally spaced arms, a pair of jaws pivoted for upward movement from said arms for engaging a mast section therebetween, means restraining said jaws against rotation below said arms, said jaws having concave gripping surfaces defining a generally circular space therebetween of smaller cross section than the mast sections to be handled whereby the weight of a mast section disposed therebetween urges said jaws into tightly gripping relation with the mast section upon elevation of said elevator cylinder, said jaws being shifted into sliding contact with mast sections therebetween on relative downward movement of said frame, and guide means projecting laterally from the upper end of said tubular post in alignment with said jaws for slidably receiving a mast section and retaining the same in vertical alignment with said post, said slot being of a length at least as great as the length of the mast sections to be hoisted to enable said pair of jaws to engage a lower end portion of the mast section at its lower limit of travel and elevate the lower end portion to a sulficient height at the upper limit of travel of said pair of jaws to enable another mast section to be disposed below and in alignment with the elevated section and their threaded ends intercoupled while the elevated section is held by said pair of jaws.

References Cited in the file of this patent UNITED STATES PATENTS 665,757 Rynearson Jan. 8, 1901 742,437 Hunter Oct. 27, 1903 874,086 Kimbro Dec. 17, 1907 989,744 Wilmot Apr. 18, 1911 2,482,950 Toftey Sept. 27, 1949 

